Surface Plasmon Polariton Propagation and Coupling in Gold Nanostructures
Surface Plasmon Polariton Propagation and Coupling in Gold Nanostructures
复制标题
DOI：
10.1021/jp501629w
复制
发表时间：
2014-04
影响因子：
3.7
通讯作者：
Kuai Yu;M. S. Devadas;Todd A. Major;S. Lo;G. Hartland
中科院分区：
文献类型：
--
作者：
Kuai Yu;M. S. Devadas;Todd A. Major;S. Lo;G. Hartland
利用扫描瞬态吸收显微镜研究了化学合成的金纳米棒中的表面等离子体激元（SPP）传播。SPP传播长度与纳米棒的大小和形状相关，这是由原子力显微镜测定的。平均传输长度为12 ± 4 μm，测量值与激发偏振无关。在玻璃衬底存在下对金纳米棒进行有限元计算以模拟实验结果。实验结果与理论计算结果的比较表明，束缚和泄漏SPP模式都可以被激发。在较大的纳米棒（宽度大于500 nm）中检测到泄漏模式，并且在较小的纳米棒中检测到束缚模式。在实验中还观察到金纳米棒和附近的金纳米片之间的高度定向和有效的等离子体激元耦合。
Surface plasmon polariton (SPP) propagation in chemically synthesized gold nanobars was investigated using scanning transient absorption microscopy. The SPP propagation lengths were correlated to the size and shape of the nanobars, which were determined by atomic force microscopy. The average propagation length was found to be 12 ± 4 μm, and the measured values were independent of the excitation polarization. Finite element calculations were performed for gold nanobars in the presence of a glass substrate to model the experimental results. Comparison between the experimental and theoretical results shows that both bound and leaky SPP modes can be excited. The leaky mode is detected in the larger nanobars (widths greater than 500 nm), and the bound mode is detected in smaller nanobars. Highly directional and efficient plasmon coupling between a gold nanobar and a nearby gold nanoplate was also observed in the experiments.